This invention relates to school and transit bus roofs. More specifically, the invention involves an improvement to roofs for these mobile vehicles for the purpose of reducing moisture intrusion into the vehicles. The new roof is essentially a single integral sheet installed without the need for multiple holes and rivets.
Owners of school and commercial or transit buses have sometimes experienced leakage of moisture or water into the bus body passenger compartments. The nearly one thousand rivets and numerous joined parts in the traditional bus roof may result in leaks, high labor, and part costs. FIG. 1 shows such a prior art commercial bus 201. The prior art design bus body 202 roofs consisted of multiple sheets 203a, 203b, 203c, and 203d of metal to comprise the roof. This prior art design called for expanding sealant between skin panels and the interior structure. The rivets 205 and 207 were installed between the sheets 203a, 203b, 203c, and 203d and the interior structure at the overlapping edges 204 and 206. After the bus has been painted, workers apply additional sealant along the edges 204 and 206 of the joints. The large number of rivets 205 and 207 and the process and lack of easy access to properly apply the rivets 205 and 207 directly and perpendicular to the rivet holes increases the probability of leakage at the rivet holes and associated joints. A relatively large amount of original manufacturer rework is associated with this work. Variances in the amount of sealant applied also contribute to the leakage issues. The roof structure did not take advantage of incorporating upper body cowl 210 and window 208 and 209 installation into its construction. What has not been previously suggested is having an integral unitized roof structure for a school or commercial bus that reduces or eliminates the opportunity for leakage by replacing rivets with adhesive or adhesive tape as the joining force between the roof skin and supporting structure and by decreasing the number of potential leakage points by decreasing the number of parts making up the roof from many overlapping panels to what is effectively a single sheet.
The roof and mounting structure of this invention and a school or commercial bus vehicle with these components installed satisfy the primary objective of this invention as follows. The roof is an integral unitized roof structure that reduces or eliminates the opportunity for leakage by replacing rivets with adhesive or adhesive tape as the joining force between the roof skin and supporting structure and by decreasing the number of potential leakage points by decreasing the number of parts making up the roof from many overlapping panels to what is effectively a single sheet. This single unitized roof may actually be comprised of two strips of metal welded together or crimped together along a seam.